Video disc with a dielectric layer formed from acetylene and nitrogen

Abstract

This invention relates to a video disc with a thin polymeric dielectric layer formed from acetylene and nitrogen in a glow discharge. The dielectric layer has improved age deterioration resistance and wear characteristics and can be prepared with low power levels.

What is claimed is: 
     
       1. A capacitive recording means comprising a disc having a spiral groove on a face thereof with audio/video information in the form of geometric variations in said groove, a thin conductive layer thereon and a thin dielectric layer formed from acetylene and nitrogen in a glow discharge on said conductive layer. 
     
     
       2. A recording means according to claim 1 wherein the dielectric layer contains from about 1.5 to about 8 atomic percent of nitrogen. 
     
     
       3. A recording means according to claim 1 wherein the dielectric layer contains from about 2.5 to about 5 atomic percent of nitrogen. 
     
     
       4. A recording means according to claim 1 wherein the dielectric layer is about 50 to about 500 angstroms thick. 
     
     
       5. A recording means according to claim 1 wherein the conductive layer is a bilayer of a first copper layer and a nickel/chromium/iron alloy layer wherein the iron content is less than 10 percent by weight and the oxygen content is about 5 to about 20 atomic percent. 
     
     
       6. A recording means according to claim 5 wherein the copper layer is from about 25 to 50 angstroms thick and the alloy layer is from about 100 to 400 angstoms thick. 
     
     
       7. A capacitive recording means according to claim 1 wherein the recording means has a lubricant layer on said dielectric layer. 
     
     
       8. A capacitive recording means according to claim 7 wherein the lubricant layer is from about 90 to about 400 angstroms thick. 
     
     
       9. A capacitive recording means according to claim 7 wherein the lubricant layer is from about 200 to about 250 angstroms thick. 
     
     
       10. A capacitive recording means according to claim 7 wherein the lubricant layer is a silicon compound having the formula ##STR3## wherein R is an alkyl group of 4-20 carbon atoms and x is an integer.